Extending mobile communications network coverage, increasing network capacity, and increasing the variety of devices served are all aspects for which improvement is desired of next generation mobile communications networks. This increase in capacity and variety of devices may in turn lead to a significant increase in the number of communications devices served by mobile communications networks. For example, the increased capacity and coverage of next generation communications networks such as 3GPP long term evolution (LTE) have led to proposals for the use of machine type communications (MTC) devices. MTC devices are typically low-data rate devices that only occasionally communicate with infrastructure equipment in a communications network and may for example be smart utility meters and information gathering devices in cars or personal medical equipment. Accordingly, because of the potential ubiquity of MTC devices, their use may lead to large increases in the number of communications devices being served by a network.
It is known that a communication terminal may access more than one communications network to transmit or to receive data, and furthermore the communications networks may be of different types. These may be 3GPP communications networks or non-3GPP communications networks. At present a communications terminal is arranged to attach to a particular network for communicating data in accordance with rules determined by an Access Network Discovery and Selection Function (ANDSF), which is programmed by an operator which has provided the communications terminal to a user.